I had heart pain every day for roughly three straight years. After starting taurine powder, it mostly went away. I've been taking it for two and a half months and have only had 7 days with some milder heart pain in that timeframe. I take 1.5g every morning and most nights, I take 1.5g before bed as well. I usually feel a bit drowsy an hour after taking it and it lasts for less than an hour. I haven't stopped taking it so I'm not sure if the improvements will hold once I stop but I don't plan on stopping in the near future. As with everything long covid, YMMV. I've responded poorly to other supplements that people have recommended but taurine powder feels like a winner for me.